Clarke: not much hugging was involved because of how busy she way, but when she wasn't she'd wrap her arms securely around your waist and tug you close
Octavia: she absolutely loved to hug. She'd always find a way to wrap herself into your arms whether she was sad or just wanted a hug she'd find a way to make you.
Raven: most of the time she'd surprise you with hugs. You'd be working on something and she'd hook her arms around your waist from behind and kiss your cheek, neck and whisper in your ear.
Lexa: Hugs were hardly something you did. She'd let her arm fall around your shoulders and lean you closer to her. But behind closed doors hugging wasn't the only thing done.